Mining giant Rio Tinto is to tap the US bond market with three fixed-rate bond issues due to mature in five, 10 and 30 years, respectively.Rio Tinto is seeking to raise $3.0bn through the issue of bonds with a weighted average coupon of 2.67% and a weighted average maturity of 12.9 years.The offering comprises: $1.25bn of five-year bonds with a coupon of 1.625%; $1.0bn of 2.875% 10-year bonds; and $750m of 30-year SEC-registered debt securities carrying a coupon of 4.125%. JH